1. Field of the Invention
The invention relates a connector to provide strain relief for large diameter wires, such as high current battery cables, and particularly for such wires that may be subject to variation in outer diameter.
2. Description of the Related Art
A wire includes a conductive core and an insulating coating surrounding the core. The insulation is removed near the end of the wire so that the conductive core can be connected to a terminal fitting, typically by welding, soldering or crimping. The assembly of the wire and the terminal fitting then may be mounted into a housing made of a synthetic resin or other nonconductive material. The wire, the terminal fitting and the housing form a connector that can be connected to a mating connector so that the terminal fitting of the connector is connected electrically to a mating terminal fitting in the mating connector.
Electrical connectors often are used in high vibration environments and/or in environments where forces may be exerted on the portion of the wire extending from the connector. Vibration of the connector and forces exerted on the wire can be transmitted to the welded, soldered or crimped connection between the conductive core of the wire and the terminal fitting, and can cause the electrical connection to degrade or fail. As a result, connectors that are used in a high vibration environment or in an environment where the wire may be subject to external forces typically have a strain relief feature. The strain relief feature typically involves placing one or more bends in the wire and tightly positioning the bends between rigid structures within the housing. The secure positioning of bent portions of the wire in the housing prevents or severely limits relative movement of the portion of the wire in the housing and hence eliminates or minimizes the effects of vibration or external forces on the soldered, welded or crimped connection between the conductive core of the wire and the terminal fitting.
The prior art strain relief structure described above works well on small diameter wires that can be bent easily and positioned adjacent rigid structures within the housing of the connector. However, large diameter wires, such as battery cables, are not bent easily. As result, the prior art strain relief structures that work well on small diameter wires are not well-suited for larger less pliable wires, such as high current battery cables.
Large diameter wires, such as battery cables, also are more likely to be subject to variation in outside diameter. The variations may be due to standard manufacturing tolerances or due to different manufacturing techniques used by suppliers of cables. Thus, prior art approaches for urging a wire into a specific nonlinear shape adjacent to rigid structures within the housing often will not provide the required strain relief due to variations in the outside diameter of the large diameter wire.
In view of the above, an object of the subject invention is to provide a strain relief structure that is particularly well suited for cross-sectionally large wires, such as high current battery cables.
Another object of the invention is to ensure adequate strain relief despite variations in cross-sectional dimensions of the wires or cables that extend into the housing of the connector.